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Displaying 1001 - 1025 of 2122

Differentiating Left- and Right-Handed Carbon Nanotubes by DNA

December 28, 2016
Author(s)
Ming Zheng, Geyou Ao, Jason K. Streit, Jeffrey A. Fagan
The emergence of macromolecules of defined structures is a crucial step in the evolution of life. The mechanism by which these structures are selected from astronomical numbers of biopolymer sequences has long been a topic of controversy1,2. Experimenting

Generalized entropy theory of glass-formation in fully flexible polymer melts

December 21, 2016
Author(s)
Jack F. Douglas, Wensheng Xu, Karl Freed
The generalized entropy theory (GET) offers many insights into how molecular parameters influence polymer glass-formation. Given the fact that chain rigidity often plays a critical role in understanding the glass- formation of polymer materials, the GET

Laser-assisted atom probe tomography of Ti/TiN films deposited on Si

December 21, 2016
Author(s)
Norman A. Sanford, Paul T. Blanchard, Ryan M. White, Michael R. Vissers, Albert Davydov, D R. Diercks, David P. Pappas
Laser-assisted atom probe tomography (L-APT) was used to examine superconducting TiN/Ti/TiN trilayer films with nominal respective thicknesses of 5/5/5 (nm). The trilayers were deposited on Si substrates by reactive sputtering. Electron energy loss

Entropy Theory of Polymer Glass-Formation in Variable Spatial Dimension

December 20, 2016
Author(s)
Jack F. Douglas, Wensheng Xu, Karl Freed
The importance of packing frustration is broadly appreciated to be an important aspect of glass formation. Recently, great interest has focused on probing the dependence on spatial dimension d as a theoretical tool for exploring essential aspects of glass

Introduction to the special issue on small-angle scattering

December 19, 2016
Author(s)
Michael Gradzielski, Andrew J. Allen
This is the foreword for a Special Issue of the Journal of Applied Crystallography on Small-Angle Scattering. This special issue collects together full-length peer-reviewed research papers in association with the 15th International Conference on Small

Analytical Multimode Scanning and Transmission Electron Imaging and Tomography of Multiscale Structural Architectures of Sulfur Copolymer-Based Composite Cathodes for Next Generation High-Energy Density Li-S Batteries

December 17, 2016
Author(s)
Vladimir P. Oleshko, Andrew A. Herzing, Christopher L. Soles, Jared J. Griebel, Woo J. Chung, Adam G. Simmonds, Jeff Pyun
Poly(sulfur-random-(1,3-diisopropenylbenzene) copolymers synthesized via inverse vulcanization represent an emerging class of electrochemically active polymers recently used in cathodes for Li-S batteries, capable of realizing enhanced capacity retention

Bound Layers Cloak Nanoparticles in Strongly Interacting Polymer Nanocomposites

December 16, 2016
Author(s)
Jack F. Douglas, Francis W. Starr, Sanat K. Kumar
Polymer-nanoparticle (NP) interfacial interactions are expected to strongly influence the properties of nanocomposites, but surprisingly, experiments often report small or no changes in the glass transition temperature, Tg. To understand this paradoxical

Effect of oxygen pressure on structure and ionic conductivity of epitaxial Li0.33La0.55TiO3 solid electrolyte thin films produced by pulsed laser deposition

December 16, 2016
Author(s)
Leonid A. Bendersky, Bharathi Kamala, Haiyan Tan, Saya Takeuchi, Haoting Shen, Jongmoon Shin, I. Takeuchi
We report on the ionic conductivity and the effect of oxygen partial pressure during the growth of Li0.33La0.55TiO3 (LLTO) epitaxial films grown on SrTiO3 (STO) (100) and (111) substrates and explore some distinct conductivity behavior. The films are

Trapping States of Mixed-Isomer Organic Semiconductors within Organic Field-Effect Transistors

December 14, 2016
Author(s)
Peter Diemer, Jacori Hayes, Evan Welchman, Rawad Hallani, Sujitra Pookpanratana, Christina Hacker, Curt A. Richter, Timo Thonhauser, Oana Jurchescu
Organic field effect transistor (OFET) performance is dictated by the composition and geometry of the device, as well as the quality of the organic semiconductor (OSC) film, which strongly depends on the purity and structural defects. When present, these

Enriching and purifying silicon epilayers for quantum information

December 6, 2016
Author(s)
Joshua M. Pomeroy, Kevin J. Dwyer, Ke Tang, Hyun S. Kim, Aruna N. Ramanayaka, David S. Simons
High quality, enriched silicon contains an exceptionally low density of defects and unpaired electron and nuclear spins that allow candidate qubits (single donors or quantum dots) to exhibit very long dephasing times compared to silicon with a natural

Communication-Comparison of Nanoscale Focused Ion Beam and Electrochemical Lithiation in beta-Sn Microspheres

December 5, 2016
Author(s)
Saya Takeuchi, William R. McGehee, Jennifer L. Schaefer, Truman M. Wilson, Kevin A. Twedt, Christopher L. Soles, Vladimir P. Oleshko, Eddie H. Chang, Jabez J. McClelland
The development of Li focused ion beams (Li-FIB) enables controlled Li ion insertion into materials with nanoscale resolution. We take the first step toward establishing the relevance of the Li-FIB for studies of ion dynamics in electrochemically active

First-principles phase diagram calculations for the carbonate quasibinary systems CaCO(sub3)-ZnCO(sub3), CdCO(sub3)-ZnCO(Sub3), CaCO(sub3)-CdCO(sub3) and MgCO(Sub3)-ZnCO(sub3)

December 2, 2016
Author(s)
Z.T.Y. Liu, Benjamin P. Burton, S. V. Khare, P. Sarin
Quasibinary solid solutions of calcite-structure carbonate minerals play an important role in rock formation. We have investigated solid solutions with cations such as Ca, Cd, Mg and Zn by performing first-principles phase diagram calculations for Ca1

Absence of Long-Wavelength Nematic Fluctuations in LiFeAs

December 1, 2016
Author(s)
Adrian Merritt, Jose Rodriguez Rivera, Yu Li, Weiyi Wang, Chenglin Zhang, Pengcheng Dai, Dmitry Reznik
We investigated long-wavelength nematic fluctuations in an Fe-based superconductor LiFeAs near q=(0.05,0,0) by measuring temperature-dependent renormalization of acoustic phonons through inelastic neutron scattering. We found that the phonons have

Characterization of Yttrium-Rich Precipitate Phases in a Titanium Alloy Weld

December 1, 2016
Author(s)
Andrew Herzing, Ratna P. Kolli, Sreeramamurthy Ankem
The yttrium-rich (Y-rich) precipitates that form in the fusion zone (FZ) of a Ti-5111 alloy weld were characterized by atom probe tomography and scanning transmission electron microscopy. Two distinct types of precipitates were identified: (1) a higher

Scalable Manufacturing of Layer-by-Layer Membranes for Water Purification

December 1, 2016
Author(s)
Christopher M. Stafford
Water is critical to the health and security of our nation. And as our population expands and water scarcity becomes a reality, we as a people need to think creatively on how we safeguard access to clean water. The manufacturing of today’s state-of-the-art

Structural Analysis of Dendrimers Based on Polyhedral Oligomeric Silsesquioxane and their Assemblies in Solution by Small-Angle Neutron Scattering: Fits to a Modified Two Correlation Lengths Model

December 1, 2016
Author(s)
Guangcui Yuan, Xing Wang, Decheng Wu, Boualem Hammouda
The small-angle neutron scattering (SANS) technique has been used to investigate the structure of dendrimers based on polyhedral oligomeric silsequioxane (POSS). Three generations and two distinct terminal groups (either vinyl or polyethylene glycol (PEG)

Complex Arrangement of Orthogonal Columns via a Supramolecular Orientational Memory Effect

November 22, 2016
Author(s)
Mihai Peterca, Mohammad Imam, Steven Hudson, Benjamin Partridge, D Sahoo, Paul A. Heiney, M L. Klein, Virgil Percec
Memory effects, including shape, chiral and liquid crystalline, enabled macroscopic materials with novel functions. However, the generation of complex supramolecular nanosystems via memory effects was not investigated. Here we report a cyclotriveratrylene

Concurrent Magnetic and Structural Reconstructions at the Interface of (111)-Oriented La 0.07 Sr 0.3 MnO 3 /LaFeO 3

November 21, 2016
Author(s)
I. Hallsteinsen, M. Moreau, Alexander Grutter, M. Nord, P.-E. Vullum, Dustin A. Gilbert, T. Bolstad, J. K. Grepstad, R. Holmestad, S. M. Selbach, A. T. N'Diaye, Brian Kirby, E. Arenholz, T. Tybell
We observe an induced switchable magnetic moment of 1.6 ± 0.40 υ B/Fe in the nominally antiferromagnetic LaFeOd3^/La 0.7Sr 0.3MnO 3/SrTiO 3(111). The magnetic reconstruction is driven by a mismatch of oxygen octahedra rotations resulting in an atomic

Jetting Flow of a Shear Banding Fluid

November 20, 2016
Author(s)
Paul NMN Salipante, Charles A. Little, Steven D Hudson
In this video we show the jetting behavior of a shear banding worm-like micelle solution in microfluidic flows. The jetting behavior is characterized by a self-contained portion of the channel where the flow velocity is greater than the surroundings. We
Displaying 1001 - 1025 of 2122